Now showing items 1-8 of 8

    • LOFAR facet calibration 

      Van Weeren, R. J.; Williams, W. L.; Hardcastle, M.J.; Shimwell, T. W.; Rafferty, D. A.; Sabater, J.; Heald, G.; Sridhar, S. S.; Dijkema, T. J.; Brunetti, G.; Brüggen, M.; Andrade-Santos, F.; Ogrean, G. A.; Röttgering, H. J. A.; Dawson, W. A.; Forman, W.R.; Gasperin, F. de; Jones, C.; Miley, G.K.; Rudnick, L.; Sarazin, C.L.; Bonafede, A.; Best, P. N.; Bîrzan, L.; Cassano, R.; Chyży, K. T.; Croston, J. H.; Ensslin, T.; Ferrari, C.; Hoeft, M.; Horellou, C.; Jarvis, M.J.; Kraft, R.P.; Mevius, M.; Intema, H. T.; Murray, S. S.; Orrú, E.; Pizzo, R.; Simionescu, A.; Stroe, A.; Tol, S. van der; White, G.J. (2016-03-07)
      LOFAR, the Low-Frequency Array, is a powerful new radio telescope operating between 10 and 240 MHz. LOFAR allows detailed sensitive high-resolution studies of the low-frequency radio sky. At the same time LOFAR also provides ...
    • LOFAR imaging of Cygnus A - direct detection of a turnover in the hotspot radio spectra 

      McKean, J. P.; Godfrey, L. E H; Vegetti, S.; Wise, Michael W.; Morganti, R.; Hardcastle, M. J.; Rafferty, D.; Avruch, I. M.; Beck, R.; Bell, M. E.; Bemmel, I. M. van; Bentum, M. J.; Bernardi, G.; Best, Philip; Blaauw, R.; Bonafede, A.; Breitling, F.; Broderick, J. W.; Brüggen, Marcus; Cerrigone, L.; Ciardi, B.; De Gasperin, Francesco; Deller, A.; Duscha, S.; Engels, D.; Falcke, H.; Fallows, R. A.; Frieswijk, W.; Garrett, M.A.; Grießmeier, J. -M.; Haarlem, M. P. van; Heald, G.; Hoeft, Matthias; van der, HorstA J.; Iacobelli, M.; Interna, H.; Juette, E.; Karastergiou, A.; Kondratiev, V. I.; Koopmans, L. V E; Kuniyoshi, M.; Kuper, G.; Van Leeuwen, J.; Maat, P.; Mann, R. G.; Markoff, S.; McFadden, R.; McKay-Bukowski, D.; Mulcahy, D. D.; Munk, H.; Nelles, A.; Orru, E.; Paas, H.; Pandey-Pommier, M.; Pietka, M.; Pizzo, R.; Polatidis, A. G.; Reich, W.; Rottgering, H. J. A.; Rowlinson, A.; Scaife, A. M M; Serylak, M.; Shulevski, Alexander; Sluman, J.; Smirnov, O.; Steinmetz, M.; Stewart, A. J.; Swinbank, J.; Tagger, M.; Thoudam, S.; Toribio, M. C.; Vermeulen, R.; Vocks, C.; Van Weeren, R. J.; Wucknitz, O.; Yatawatta, S.; Zarka, P. (2016-12-01)
      The low-frequency radio spectra of the hotspots within powerful radio galaxies can provide valuable information about the physical processes operating at the site of the jet termination. These processes are responsible for ...
    • The LOFAR LBA Sky Survey I. survey description and preliminary data release 

      Gasperin, F. de; Williams, W. L.; Best, P.; Bruggen, M.; Brunetti, G.; Cuciti, V.; Dijkema, T. J.; Hardcastle, M. J.; Norden, M. J.; Offringa, A.; Shimwell, T.; Weeren, R. van; Bomans, D.; Bonafede, A.; Botteon, A.; Callingham, J. R.; Cassano, R.; Chyzy, K. T.; Emig, K. L.; Edler, H.; Haverkorn, M.; Heald, G.; Heesen, V.; Iacobelli, M.; Intema, H. T.; Kadler, M.; Malek, K.; Mevius, M.; Miley, G.; Mingo, B.; Morabito, L. K.; Sabater, J.; Morganti, R.; Orru, E.; Pizzo, R.; Prandoni, I.; Shulevski, A.; Tasse, C.; Vaccari, M.; Zarka, P.; Rottgering, H. (2021-02-17)
      Context. The LOw Frequency ARray (LOFAR)istheonlyradiotelescopethatispresentlycapableofhigh-sensitivity,high-resolution (i.e. < 1mJybeam−1 and < 1500) observations at ultra-low frequencies(< 100MHz). To utilise these ...
    • LOFAR MSSS: Discovery of a 2.56 Mpc giant radio galaxy associated with a disturbed galaxy group 

      Clarke, A. O.; Heald, G.; Jarrett, T.; Bray, J. D.; Hardcastle, Martin; Cantwell, T. M.; Scaife, A. M. M.; Brienza, M.; Bonafede, A.; Breton, R. P.; Broderick, J. W.; Carbone, D.; Croston, J. H.; Farnes, J. S.; Harwood, J. J.; Heesen, V.; Horneffer, A.; Horst, A. J. van der; Iacobelli, M.; Jurusik, W.; Kokotanekov, G.; McKean, J. P.; Morabito, L. K.; Mulcahy, D. D.; Nikiel-Wroczynski, B. S.; Orru, E.; Paladino, R.; Pandey-Pommier, M.; Pietka, M.; Pizzo, R.; Pratley, L.; Riseley, C. J.; Rottgering, H. J. A.; Rowlinson, A.; Sabater, J.; Sendlinger, K.; Shulevski, A.; Sridhar, S. S.; Stewart, A. J.; Tasse, C.; Velzen, S. van; Weeren, R. J. van; Wise, M. W. (2017-05-01)
      We report on the discovery in the LOFAR Multifrequency Snapshot Sky Survey (MSSS) of a giant radio galaxy (GRG) with a projected size of $2.56 \pm 0.07$ Mpc projected on the sky. It is associated with the galaxy triplet ...
    • LOFAR MSSS: Flattening low-frequency radio continuum spectra of nearby galaxies 

      Chyży, K. T.; Jurusik, W.; Piotrowska, J.; Nikiel-Wroczyński, B.; Heesen, V.; Vacca, V.; Nowak, N.; Paladino, R.; Surma, P.; Sridhar, S. S.; Heald, G.; Beck, R.; Conway, J.; Sendlinger, K.; Curyło, M.; Mulcahy, D.; Broderick, J. W.; Hardcastle, M. J.; Callingham, J. R.; Gürkan, G.; Iacobelli, M.; Röttgering, H. J. A.; Adebahr, B.; Shulevski, A.; Dettmar, R. -J.; Breton, R. P.; Clarke, A. O.; Farnes, J. S.; Orrú, E.; Pandey, V. N.; Pandey-Pommier, M.; Pizzo, R.; Riseley, C. J.; Rowlinson, A.; Scaife, A. M. M.; Stewart, A. J.; Horst, A. J. van der; Weeren, R. J. van (2018-11-07)
      Aims. The shape of low-frequency radio continuum spectra of normal galaxies is not well understood, the key question being the role of physical processes such as thermal absorption in shaping them. In this work we take ...
    • LOFAR MSSS: The Scaling Relation between AGN Cavity Power and Radio Luminosity at Low Radio Frequencies 

      Kokotanekov, G.; Wise, Michael; Heald, G. H.; McKean, J. P.; Bîrzan, L.; Rafferty, D. A.; Godfrey, L. E H; Vries, M. de; Intema, Huib T.; Broderick, J. W.; Hardcastle, M. J.; Bonafede, A.; Clarke, A. O.; Weeren, R. J. van; Röttgering, H.~J.~A.; Pizzo, R.; Iacobelli, M.; Orrú, E.; Shulevski, Alexander; Riseley, C. J.; Breton, R. P.; Nikiel-Wroczyński, B.; Sridhar, S. S.; Stewart, A. J.; Rowlinson, A.; Horst, A. J. van der; Harwood, J. J.; Gürkan, G.; Carbone, D.; Pandey-Pommier, M.; Tasse, C.; Scaife, A. M. M.; Pratley, L.; Ferrari, Chiara; Croston, J. H.; Pandey, V. N.; Jurusik, W.; Mulcahy, D. D. (2017-09-07)
      We present a new analysis of the widely used relation between cavity power and radio luminosity in clusters of galaxies with evidence for strong AGN feedback. We study the correlation at low radio frequencies using two new ...
    • LOFAR, VLA, and Chandra observations of the Toothbrush galaxy cluster 

      Van Weeren, R. J.; Brunetti, G.; Brüggen, M.; Andrade-Santos, F.; Ogrean, G. A.; Williams, W. L.; Röttgering, H. J. A.; Dawson, W. A.; Forman, W.R.; Gasperin, F. de; Hardcastle, M.J.; Jones, C.; Miley, G.K.; Rafferty, D. A.; Rudnick, L.; Sabater, J.; Sarazin, C.L.; Shimwell, T. W.; Bonafede, A.; Best, P. N.; Bîrzan, L.; Cassano, R.; Chyży, K. T.; Croston, J. H.; Dijkema, T. J.; Ensslin, T.; Ferrari, C.; Heald, G.; Hoeft, M.; Horellou, C.; Jarvis, M.J.; Kraft, R.P.; Mevius, M.; Intema, H. T.; Murray, S. S.; Orrú, E.; Pizzo, R.; Sridhar, S. S.; Simionescu, A.; Stroe, A.; Tol, S. van der; White, G.J. (2016-02-22)
      We present deep LOFAR observations between 120-181 MHz of the "Toothbrush" (RX J0603.3+4214), a cluster that contains one of the brightest radio relic sources known. Our LOFAR observations exploit a new and novel calibration ...
    • A plethora of diffuse steep spectrum radio sources in Abell 2034 revealed by LOFAR 

      Shimwell, T. W.; Luckin, J.; Brüggen, M.; Brunetti, G.; Intema, H. T.; Owers, M. S.; Röttgering, H. J. A.; Stroe, A.; Weeren, R. J. van; Williams, W. L.; Cassano, R.; Gasperin, F. de; Heald, G. H.; Hoang, D. N.; Hardcastle, M.J.; Sridhar, S. S.; Sabater, J.; Best, P. N.; Bonafede, A.; Chyży, K. T.; Ensslin, T. A.; Ferrari, C.; Haverkorn, M.; Hoeft, M.; Horellou, C.; McKean, J. P.; Morabito, L. K.; Orrù, E.; Pizzo, R.; Retana-Montenegro, E.; White, G.J. (2016-06-11)
      With Low-Frequency Array (LOFAR) observations, we have discovered a diverse assembly of steep spectrum emission that is apparently associated with the intra cluster medium (ICM) of the merging galaxy cluster Abell 2034. ...